The overprescription of antibiotics by primary care physicians is a growing problem in the United States. Overprescribing specifically refers to providing a prescription of antibiotics for illnesses such as those caused by viruses where antibiotic use is ineffective. Widespread overprescribing among primary care physicians has led to antibiotic resistance among various strains of bacteria. The escalating problem of antibiotic resistance among these organisms poses a threat to public health since infections caused by such organisms are more difficult to treat and frequently cause more serious and longer term illnesses. This problem has persisted despite studies which indicate that this practice is highly problematic. Recent research showed that when pediatricians perceive a parental expectation for antibiotics, they are significantly more likely to overprescribe. It is hypothesized that parents' communication behaviours act as the vehicle by which parent pressure - whether actual or perceived - is communicated to physicians. Additionally, it is through parent-physician communication that a decision to prescribe antibiotics or not is made. Four areas of communication have been identified where particular behaviours are hypothesized to be related to parent pressure, physician's perceptions of parent pressure and the physician's communication of their treatment decisions: 1) the way parents and children describe their reason for visiting the doctor, 2) the manner in which parents respond to history taking questions, 3) the way physicians explain to the parent what the diagnosis is and what treatment should be given, and 4) whether parents resist the physician's delivery of diagnosis and treatment information. This communication focus is intended to provide a better understanding of how parents and pediatricians negotiate the prescription of antibiotics. The data for this project include 306 transcribed pediatric acute care encounters. This data will be used in combination with already existing survey data to 1) examine how physicians respond to parent's communiction behaviours which indicate a preference for antibiotic prescription medication 2) examine the relationship between a) parent preferences for antibiotics and doctor perceptions of these preferences and b) parents' formulations of the child's problem 3) examine the relationship between a) parent preferences for antibiotics and doctor perceptions of these preferences and b) parents' statements of concern about their children's conditions during history taking and 4) examine the relationship between doctor's offers of diagnostic and treatment information and parents' behaviours which index their preferences for antibiotic prescription medication. The knowledge gained from this study will ultimately aid in the development of an intervention to change pediatrician antibiotic prescribing practices.